hypenator.cc errors

Greets all,

Another sequence of bads that cropped up using the Silicon
Graphics MIPSpro compiler, any thoughts? To wit:

cc-1028 CC: ERROR File = hyphenator.cc, Line = 147
  The expression used must have a constant value.

     char chars [l + 1];
                 ^

cc-1028 CC: ERROR File = hyphenator.cc, Line = 185
  The expression used must have a constant value.

     char noHyphens[len - 2 * breaks->size() + 1];
                    ^

cc-1028 CC: ERROR File = hyphenator.cc, Line = 185
  The expression used must have a constant value.

     char noHyphens[len - 2 * breaks->size() + 1];
                              ^

cc-1060 CC: ERROR File = hyphenator.cc, Line = 185
  The indicated operator is not allowed in an integral
constant expression.

     char noHyphens[len - 2 * breaks->size() + 1];
                                    ^

cc-1059 CC: ERROR File = hyphenator.cc, Line = 185
  A function call is not allowed in a constant expression.

     char noHyphens[len - 2 * breaks->size() + 1];
                              ^

cc-1028 CC: ERROR File = hyphenator.cc, Line = 316
  The expression used must have a constant value.

     char work[strlen (wordLc) + 3];
               ^

cc-1059 CC: ERROR File = hyphenator.cc, Line = 316
  A function call is not allowed in a constant expression.

     char work[strlen (wordLc) + 3];
               ^

cc-1028 CC: ERROR File = hyphenator.cc, Line = 316
  The expression used must have a constant value.

     char work[strlen (wordLc) + 3];
                       ^

8 errors detected in the compilation of "hyphenator.cc".
make: *** [hyphenator.o] Error 2